Yes it does. We are using eggOn together with eggplannt drive (the command line API) by using just the execution license. Whenever you send any command over the drive to eggon it takes a screenshot from the ios device. This makes it impossible to click faster than screenshotting takes.

Yey, but you see this happens when no update is needed. It makes eggon quite useless for some test cases. Some commands where you just click on a coordinate should not require update from vnc server. Isnt this quite obvious or what?

It's built into eggPlant that it gets an update before interacting with the SUT. I think it's the nature of how the screen buffer is accessed on iOS that there isn't any choice but to get the whole screen -- there are no incremental updates available.